Oscillating air engine



July 1, 1930;

N. KOEHN OSCILLATING AI R' ENGINE Filed Aug, 17; 1925 5 m R N m T w n/76,14 F m M v A 3 I a Q m m M n PW N nially spring pressedagainstaneedle toclose are stationary in relationto-.theJcasing .1 1

' 3 Y variousdetails and features of improvethe lower cylinder. In thisslot there isiinthe neutral position." I I PatentedJuly L 1930 l l p Q INITED STATES. JOFFIC E" NATHANIEL KOEI-IN, or oA L irip CALIFORNIA v'osoILLA'rIne m anem a: v A lication filed August 17, 1925. Serial No.50,661.

Myinvention is an oscillating air engine Figure 5 is a view similar toFigure t particularly. adapted to form a hand tool. showing the uppervalve in the position of The engineoscillates througha partial cirinletto'the leftiside of the valve plates and cle and the speed can, to acertain extent, the outlet valve in the position of outlet 5 beregulated by the resistance to the oscilla-v from the right hand side. 7tion. My invention is particularly adapted Figure 6 is an elevation ofthe pistons'and for use to operate valve grinding or similar theircarrying yokes attached to the drive tools. p Y shaft. I p v Myinventioncomprisesin brief ,a casing Figure, 7 is an elevation of one end of a:10 having upperand lower-stationary cylinders piston as if taken on theline 7 --7 of Figmounted therein with 'an oscillating shaft ure 2indicating the attaching socket screw 7 extending axially through thelower end of and the duplex springs housed therein to the casing and thelowerand upper cylactuate-the valves. y inders. The cylinders have anannular re-, Figure 8 is a side elevation. of the dia cess and supportan airductwhich ispro phragm needle valve. i vided with air inlet andoutlet valve seats R ferring particularly to Figures 1 and E in whichare positioned loosely operating my 1 oscillating airi engineisillustrated as valves. A pairof pistons are; supported by formed with anoutsidecasing. 1 which curvedarins from the central shaftand areispreferably knur 1 outside'to form 'adapted to oscillate intherre'cesses-or air ahand grip and made circular on its eX- 7 chambersin the upperand lower. cylinders. terior face. The casing has a;:closure.Theair pressure for operating theipistonsis formed integral; therewithand is alsoprodeveloped on opposite sides of the air duct, vided with anaperture 3 extending the re-* or passage,' and on the opposite sides ofthe through for the drive shaft n The 25 valve seats so that thepistonsv are turned casingis preferably cylindrical on itsxinthrough a certainangle by the airacting on side surface and forms the housing forlowerone piston-and then on the other; and upper cylinders?) and 6andalsoforms The'air inlet from a compressoris cona piston chamber bythe annuIar lower trolled by a diaphragm valve which is norand-upperrecesses 8 and 9. -These cylinders a needle valve and onf' a slightretardingof and-in practice made to have altight pressed the shaft airpressure builds up sufiicient he cylinders are formed with avertitoraise" the diaphragm and thus. open'the c'a'ljslot, lOextending from theupper surface needle valve to .a greater extent. of the upper cylinderto the lower surface of nie'nt will appear from the following de sorteda pair of valve plates 27 both made scription considered with:thedrawings, in identical whichcontain the air ductsyvalve which: Q 7 vseats, an'dhold the inlet and outletvalves Figure his a verticalsectionofFi'gure 2 as willwbe'hereafter described." onthe line 1-1 in thedirection of the, Thepistonsare constructed andinountedp arrows. I v asfollows:Thefshaftihasayokel2 secured" .Figure'2 is an enlargedhorizontal section thereto by a, stern, 18 which. passes through ofFigure 1 on the line 2' 2in the direction an aperture 1 1 in theshaftand-has a riveted of the arrows." 1:1,

' .head 15; Thepistons'l6 aresecured'tothe Figure 3 is anelevation ofthe air ducts ends of the yoke 12 which'latteron the ends in thevalveplates as if take'n in the direoof the yoke have elongated plates1'} pref I tion'of the arrow 30f Figure erably formed uintegraltherewith. As. Figure 4 is a vert cal section of Figureshown.particularlyainFigureT apiston-cup 3 on the lines 4. -4; showingthevalves' in -18- preferablyrlformed"of leatherhas its base19::positiorie'd against theplates 17 and held ner projection 26 of thesocket screw are to positively actuate the inlet and outlet,

valves as will be hereafter described.

The valve plates including the air ducts and valves are constructed asfollows: I-lav ing reference particularly to Figures 3', 4, and 5 a pairof plates 27 are both of similar construction and are so formed thatwhen placed'face to face they have a rectangular air inlet duct 28 atthe'upper end and a rectangular air outlet duct 29 at the lower end;Preferably annular apertures 30 eX- tend through the upper portions ofthe plates and have on the inside an annular recess '81 forming oppositeinlet valve seats 32. An inlet valve 33 having a central solid block'34preferably cylindrical and stems 35 extending in opposite directionstherefrom and having a sliding fit in the apertures 30 isthussupportedin the upper part ,casingand preferably at the junctionpoint of the valve plates and situated in the inlet duct. It ispreferable to form fitltlngj36 i on the stems 35 to allow sufficient airto pass from the inlet duct to the piston chamber 7, The outlet valves87 comprise two valve blocks 38 mounted on the end of a fluted stem 39.These blocks seat in annular re cesses 40 formed on the outside of theplates 27. The flutings allow the air to pass aroundthe annularapertures 41 in the lows: Having reference particularly to Figuresland"8:-A flexible diaphragm 44 is secured to a small bore tube 45 havinga solid head 46 on the lower face of the diaphragni and a clamping disc47 bearing against the upper face ofthe diaphragm.

The diaphragm isclamped at its periphery between a clamping ring 48 andescrow threaded sleeve 49. of the cap 50, this cap being secured to thecasing l 'by the screw 51 presses;

threaded sleeve. A spring against the clamping d1sc47 and a light flatannular ring 52 which'latter is thereby "positioned against the lowersurface ofthe cap 50. A spring tensioning screw-53 is threaded throughthe cap and may be adjusted to bear on one side of the ring 52 andthereby be utilized to increase or decrease the tensionon the spring.

The cap has an upward extension 53 with a socket 54 therethrough for theair inlet which latter has a valve 55 to control the opening. A valveshut off screw 56 is threaded into the interior of the spring tensioningscrew and may be positioned at different elevations to engage the curvedfinger grip of the valve 55 and therefore hold the valve for differentpositions of opening.

The lower end of the'air duct 54 has a small bore 58 in which issituated a piston 59 preferably formed of leather with upturned lips 60.This pistonis secured to the end of the small bore tube 45 by means of anut 61 screwed on the end ofsaidtube. An aperture 62 is formed in thecap to allow the free passage of any air which may leak past the piston59. An airhose will be connectedto the screw threaded end 63 of theextension 53 of the cap.

The lower end 64 of the bore 65 of the tube 45 is formed in proper shapeto make a valve seat when co-operating with the needle 66, which maybeinserted through the upper cylinder 6and adjusted therein by means ofthe screw threads 67 as shown in Figure 1. V

An oil aperture 68 is bored through the of the ilower and upper.cylinders into the piston chamber 7.

The operation of my oscillating air engine is as follows Presuming thatthe device is connected-to asource of air. and'a tool such as a valvegrinder beingfattached' to the lower end of the shaft 4 the tension ofthe spring5l is so adjusted that, the air pressure from the source ofsupplylafter the valve 55 is open the desired. amount is such that thediaphragm will be slightly liftedat a pressure'of the air on'the needle66 thereby opening the valve seat 64. This allows a certainfamount ofair to pass through the engine and willcause it to idle. 1 Whenresistance is broughtagainst the shaft-'4 by utilizing a tool thereonthe diaphragm-will be elevated to a greater extent on account of thepressure inregard to the diaphragm building up to substantially thepressure in the pipes or leading to the engine. The air passesldownwardfrom below the diaphragm through the inlet 28 andwill act on one ofthepistons 16- When the air passes through the inlet 28 and. out one sideof the upper opening in the valve plate 27, the inlet valve block 34isfor oed'or seated inthe opening in the other valve .plate27;

The pressurelof air causes the outlet valve. 374:0 seat inthe oppositemanner. As the piston is driven to oscillatein one direction forinstance in a clockw se .d1rect on, as indicated by the arrow in Figure2, at the end of the stroke the inner springs 25 will strike both theupper and lower valves, that is, the inlet and outlet valves and forcethem into the opposite positions. The valves are kept closed on theirseat by the air pressure.

The spring 25 by itself is not suflicient to fully move the valve butwhen-the spring 24L also strikes the valves and if they. still do notmove the inner projection 26 of the socket screw positively forces thevalves into the opposite seat, thereby causing the .in-

let air to fiow out of the opposite sides of the valve plates 11. It isapparent that the alternate movement of the inlet and outlet valves willcause a corresponding exhausting of the air from said valves.

It will thus be seen that the pistons will be driven alternatelv inopposite directions and at the end-of each stroke t-he springs and theprojection on the face of the pistons will idle slowly until the airvalve is closed.

Y My invention may be materially modified in main construction and indetail to suit 7 special requirements and for different sized airengines. Moreover if delicacy of operation is not required" some of theelements may be eliminated or simplified in construc- 1 tion. 7

Having described my invention, what I claim is: v I I In a device of theclass described, a cylinder, partition plates disposed in said cylinder,said partition plates adapted to rest in parallel engagement with eachother to form'a single partition wall within said cylinder, inlet andoutlet passage ways formed in said partition plates and adapted to alinewith each other for admitting air,

' valves positioned" insaid alined passageways, a rockable shaft,pistons carried by V of sprlngs positioned w1th1n said hollow ture.

said shaft and being oscillatable in said cyl-' inder, piston cupssecured to -said pistons '7 said securing means comprising hollowmembers externally screw threaded and hav-,

ing the inner ends thereof projecting in wardly beyond said piston cups,a plurality members, said springs extending beyond the ends of saidhollow members and adapteol'to i cooperate therewith to successivelyengage said valves andoperate ation of the pistons.

same. during oper- 7 In testimony whereof "I atfix f i V NATHANIEL KoEHuo i.

